1. Field of the Invention
The invention relates generally to a supporting brace for pivotally mounting a fryer lifting lid on a monorail lifting device. Further, it relates to a lifting lid assembly including a lifting lid pivotally mounted on a supporting brace and a monorail lifting device including a monorail having a receiving bracket for receiving a monorail mounting bracket positioned on the supporting bracket and manual, automatic, or manually assisted means for raising and lowering the receiving bracket along the monorail.
2. Description of Related Art
A large capacity pressure cooker or pressure fired deep fat fryer generally comprises a vat or cooking vessel of a sufficient size to receive a wire basket or tray carrier, in which the food product to be cooked is held. The basket or tray carrier is thereafter submersed in a cooking medium, such as melted shortening or cooking oil, which is contained in the cooking vessel. The cooking vessel may be closed by a lid which makes a seal with an upper edge of the cooking vessel. Alternatively, a large capacity cooker may be of an open-well design. In such cookers, the lid of the cooker is an open frame permitting direct access to the cooking vessel and to the food products submersed therein. The frame may support a wire basket for holding food products or a food tray carrier for carrying a plurality of trays containing food products. Although the frame does not form an air-tight seal with the upper edge of the cooking vessel, the frame may reduce spillage and splashing of a cooking medium from the cooking vessel during cooking.
In one known configuration, the lid lifting assembly includes a support frame vertically oriented and secured to a rearward end of the pressure cooker. The support frame comprises a pair of vertical guide rails, each having a U-shaped cross-section and opening toward each other. The guide rails are joined together at their upper and lower ends by top and bottom horizontal frame members. The front, rear, sides, and top of the support frame may be enclosed by stainless steel panels forming a lid lifting device housing, which comprises a portion of a cooker cabinet or a cooker transfer cart. A frame-like carriage is mounted vertically within the support frame. The carriage has rollers which are adapted to be received within the support frame guide rails. Consequently, the carriage may be positioned vertically within the support frame. A pair of horizontal arms is affixed to the carriage. The arms extend from the carriage toward the cooker lid through vertical slots in the stainless steel panel covering the front of the support frame. The cooking vessel lid of the pressure cooker is mounted on these horizontal arms.
A cable drum is driven by an electric motor mounted on the top horizontal frame member. In a further known configuration, a pair of cables is provided, each cable having one end attached to the drum and the other end attached to the carriage. One of the cables may be slightly longer than the other and, consequently, does not bear the weight of the carriage. The longer cable serves as a back-up cable if the primary cable fails. The drum is rotatable in a first direction by the electric motor to raise the carriage within the support frame and consequently raising the carriage arms and the lid therewith. The drum is rotatable in the opposite direction by the electric motor to lower the carriage within the support frame and to lower the arms and lid therewith. In this manner the lid of the pressure cooker is shifted between its lowered position seated upon the upper edge of the cooking vessel and its raised position.
In another known configuration, the cooker lid may be manually raised and lowered with the assistance of a counterbalance weight supported in the lid lifting device housing. With the assistance of a locking device, the cooker lid may be manually lifted and supported at various heights. Moreover, the use of a counterbalance weight has been combined with the use of an electrical motor to create a manually assisted raising and lowering means.
In a closed lid cooker, the food product is cooked for the desired length of time under both elevated heat and pressure. Following the cooking cycle, an operator may relieve the pressure in the cooking vessel and then may open the lid in order to remove the wire basket or fryer tray carrier or simply remove the food product from the wire basket or fryer tray carrier.
Because the lid must be of sufficiently heavy construction to properly and safely withstand the pressure within the cooking vessel during the cooking cycle, it may be difficult for some operators to lift the lid to load or unload the cooker, or remove the wire basket or fryer tray carrier. To overcome this problem, operators have employed various types of automatic mechanisms for opening and closing the cooker lid. In some instances, these various mechanisms are used to additionally hold the lid down and in a sealed position during the pressurized operation of the cooker.
Some known lid raising and lowering mechanisms require powerful power train means. Moreover, some of these mechanisms are positioned at the sides of or around the cooking vessel making access to the cooking vessel for loading and unloading and for cleaning difficult or awkward, or both. Electro-mechanical or hydraulic systems have been used for opening and closing the lid, but these systems have experienced significant maintenance problems and resultant down-time. In addition, some of the raising and lowering means are sufficiently complex to require a skilled operator. As a result, efforts to mechanize the operation of large capacity pressure cookers by means of electro-mechanical or hydraulic controls for raising and lowering the lids of the cooking vessels have sometimes produced more problems than they have solved. In addition, the more complex and the more exposed the raising and lowering mechanism, the more susceptible the mechanism is to the adverse effects of dust, dirt, and cooking medium residue.